An Investigation of the Mechanical Behaviors of [45/-45/0/90]ns Satin Weave Composite at Different Loading Rates

Abstract

The objective of this article is to investigate the compressive behaviors of [45/-45/0/90]ns satin weave E-7781 glass/Eepoxy composite laminate under different loading strain rates along the in-plane direction. The low strain rate tests were conducted with an INSTRON testing machine, and the high strain rate tests were conducted using a pulse shaper modified compression Split Hopkinson Pressure Bar (SHPB) apparatus. Failure strength and strain at peak stress were evaluated experimentally at different strain rates. The results showed that failure strength and strain at peak stress were rate sensitive. A few strain rate dependent constitutive models were referred to describe the dynamic mechanical behaviors of woven composites with various stacking sequence, and the constants in the equations could be confirmed from experiment data. Optical and microscopic graphs on the specimens were carefully examined to determine operative failure modes. Within the studied strain rate regimes, the failure mode was observed to change from splitting followed by fiber kink banding to predominantly delamination and shear fracture as the strain rate increases from quasi-static to high strain rates.